1. Field of the Invention
The present invention relates to a method for manufacturing a Mach-Zehnder modulator, a method for manufacturing an optical waveguide, and an optical waveguides.
2. Description of the Related Art
K. Tsuzuki, T. Ishibashi, T. Ito, S. Oku, Y. Shibata, R. Iga, Y. Kondo and Y. Tohmori, “40 Gbit/s n-i-n InP Mach-Zehnder modulator with a π voltage of 2.2 V”, Electronics Letters Online, 2 Oct. 2003, Vol. 39, No. 20. discloses a Mach-Zehnder modulator. This Mach-Zehnder modulator includes a high-mesa waveguide disposed on a semiconductor substrate. Side surfaces of the high-mesa waveguide are buried with a benzocyclobutene resin.